In mobile office environments users are frequently localized when they login at a terminal which is able to determine their position or to which their spatial or geographical position is known. However this type of user localization demands a specific action on the part of the user to activate or login at this type of terminal. In addition it is very expensive to set up, manage and update these types of localization systems.
A widely-known localization system is the GPS (Global Positioning System) which generally allows very precise localization. However, because of the low field strength of the GPS signal, it is not possible as a rule to receive this signal within a building. This means that a GPS-based localization system can generally not be used especially in the office environment and in logistics applications within buildings.